Andre Weil, brother of the philosopher Simone Weil, was one of the great mathematicians of the 20th century. He was one of the influential Bourbaki group.
A famous anecdote of his misadventures during the second world war was confirmed in his autobiography. He had travelled to Finland, and was arrested under suspicion of esponage. He was saved from being shot only by the intervention of Nevanlinna.
After the war, Weil came to the United States where he taught at the University of Chicago before settling at the Institute for Advanced Study in Princeton.
He made substantial contributions in many areas, including algebraic geometry and number theory. Among his accomplishments were discovering a profound connection between topology and number theory, formulating the so-called Weil conjectures (later proved by Grothendieck and Deligne), the ``Riemann hypothesis for function fields, laying proper foundations for algebraic geometry, and discovery that the so-called Weil representation, previously introduced in quantum mechanics by Segal and Shale, gave a proper framework for understanding the classical theory of quadratic forms.